Method for selectively depositing a Group IV semiconductor and related semiconductor device structures

ABSTRACT

A method for selectively depositing a Group IV semiconductor on a surface of a substrate is disclosed. The method may include, providing a substrate within a reaction chamber and heating the substrate to a deposition temperature. The method may further include, exposing the substrate to at least one Group IV precursor, and exposing the substrate to at least one Group IIIA halide dopant precursor. Semiconductor device structures including a Group IV semiconductor deposited by the methods of the disclosure are also provided.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

The present disclosure claims the benefit of U.S. Provisional Patent Application No. 62/534,625, filed on Jul. 19, 2017 and entitled “A METHOD FOR SELECTIVELY DEPOSITING A GROUP IV SEMICONDUCTOR AND RELATED SEMICONDUCTOR DEVICE STRUCTURES,” which is incorporated herein by reference.

FIELD OF INVENTION

The present disclosure generally relates to methods for selectively depositing a Group IV semiconductor and related semiconductor device structures. The present disclosure also generally relates to methods of doping a Group IV semiconductor and doping precursors which may be utilized for p-type doping of Group IV semiconductors.

BACKGROUND OF THE DISCLOSURE

The scaling of semiconductor device structures, such as, for example, complementary metal-oxide-semiconductor (CMOS) devices, has led to significant improvements in speed and density of integrated circuits. However, conventional device scaling faces immense challenges for future technology nodes.

One approach to improve semiconductor device performance is to enhance the carrier mobility and consequently the transistor drive current utilizing strain induced effects. For example, it has been shown that the hole mobility may be considerably enhanced in a p-channel silicon (Si) transistor employing stressor regions, such as, stressor regions employed in the source and drain regions of the transistor structure.

The contact resistance to the active regions of a semiconductor device structure may be a concern for on-going device improvement at future technology nodes. For example, for CMOS device structures, the contact resistance may include the electrical resistance between the contact structure and one or more stressor regions comprising the source and drain regions of the transistor structure. In the case of an n-type MOS device, the stressor region may comprise a highly doped region, i.e., with a carrier density of approximately 5×10²⁰ cm⁻³, doped with either phosphorus or arsenic. The high doping levels that may be achieved in the n-type MOS device stressor region may result in a contact resistivity as low as 0.3 mΩ-cm. However, for the p-type MOS device, the current state of the art has focused on the use of boron p-type doping utilizing a boron dopant precursor, such as, diborane (B₂H₆). The use of diborane (B₂H₆) in p-type MOS devices becomes prohibitive for pure Ge layers and/or as the Ge fraction is increased in Si_(1-x)Ge_(x) stressors. Efforts to increase the p-type carrier density in p-type MOS device layers by the addition of further boron may result in a decline in the crystalline quality of the doped stressor region and may not significantly contribute to the active carrier density in the p-type stressor region. Accordingly, alternative methods and precursors are desired that would enable high p-type doping densities in semiconductor materials, such as, for example, Group IV semiconductor materials.

In some applications, it may be desirable to deposit a Group IV semiconductor only in certain areas of a substrate. Typically, such a discriminating result is achieved by depositing a continuous Group IV semiconductor layer and subsequently patterning the Group IV semiconductor layer using lithography and etch steps. Such processing may be time consuming and expensive, and does not offer the precision required for many applications. A possible solution is the use of selective deposition processes whereby the Group IV semiconductor material is deposited only in the desired areas thereby eliminating the need for subsequent patterning steps. Accordingly, methods are desired that would enable not only high p-type doping densities in Group IV semiconductor materials but also enable selective deposition of such highly p-type doped Group IV semiconductor materials.

SUMMARY OF THE DISCLOSURE

In accordance with at least one embodiment of the disclosure, a method for selectively depositing a Group IV semiconductor on a surface of a substrate is disclosed. The method may comprise: providing a substrate within a reaction chamber, heating the substrate to a deposition temperature, exposing the substrate to at least one Group IV precursor, and exposing the substrate to at least one Group IIIA halide dopant precursor. The embodiments of the invention may also include a semiconductor device structure which may comprise a Group IV semiconductor deposited by the methods of the disclosure.

For purposes of summarizing the invention and the advantages achieved over the prior art, certain objects and advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught or suggested herein without necessarily achieving other objects or advantages as may be taught or suggested herein.

All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments will become readily apparent to those skilled in the art from the following detailed description of certain embodiments having reference to the attached figures, the invention not being limited to any particular embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

While the specification concludes with claims particularly pointing out and distinctly claiming what are regarded as embodiments of the invention, the advantages of embodiments of the invention may be more readily ascertained from the description of certain examples of the embodiments of the invention when read in conjunction with the accompanying drawings, in which:

FIG. 1 illustrates a process flow diagram illustrating an exemplary deposition method in accordance with embodiments of the invention; and

FIG. 2 illustrates a schematic diagram of a semiconductor device structure including a p-type doped Group IV semiconductor deposited in accordance with embodiments of the invention.

It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of illustrated embodiments of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Although certain embodiments and examples are disclosed below, it will be understood by those in the art that the invention extends beyond the specifically disclosed embodiments and/or uses of the invention and obvious modifications and equivalents thereof. Thus, it is intended that the scope of the invention disclosed should not be limited by the particular disclosed embodiments described below.

As used herein, the term “substrate” may refer to any underlying material or materials that may be used, or upon which, a device, a circuit or a film may be formed.

As used herein, the term “Group IV semiconductor” may refer to a semiconductor material comprising at least one of carbon (C), silicon (Si), germanium (Ge), tin (Sn) or alloys thereof.

As used herein, the term “Group IIIA halide dopant precursor” may refer to dopant precursor comprising a halide and a metal element, the metal element further comprising a Group IIIA metal.

As used herein, the term “monocrystalline” may refer to a material which comprises a substantial single crystal, i.e., a crystalline material which displays long range ordering. It should however be appreciated that a “monocrystalline” material may not be a perfect single crystal but may also comprise various defects, stacking faults, atomic substitutions, and the like, as long as the “monocrystalline” material exhibits long range ordering.

As used herein, the term “non-monocrystalline” may refer to a material which does not comprise a substantial single crystal, i.e., a material which displays either short range ordering or no ordering of the crystalline structure. “Non-monocrystalline” materials may comprise polycrystalline materials which may display short range ordering and amorphous materials which may display substantially no ordering of the crystalline structure.

The embodiments of the invention may include methods for depositing a Group IV semiconductor and particularly methods for depositing Group IV semiconductors comprising a Group IIIA dopant. As a non-limiting example of the embodiments of the invention, the methods may include depositing a Group IV semiconductor layer comprising a Group IIIA dopant, such as, for example, a dopant comprising one or more of aluminum (Al), gallium (Ga), or indium (In). The methods of the disclosure utilize novel Group IIIA dopant precursors, which may enable high active carrier concentrations up to, for example, active carrier concentrations of greater than approximately 1×10²⁰ cm⁻³ The methods of the disclosure may also utilize novel Group IIIA dopant precursors for achieving high active p-type carrier concentrations in Group IV semiconductors, including Group IIIA dopant precursors, such as, for example, one or more Group IIIA halide dopant precursors. The novel Group IIIA dopant precursors described herein for achieving high active p-type carrier concentrations in Group IV semiconductors may not only provide high carrier concentrations but also retain the crystalline quality of the Group IV semiconductor. For example, Group IV semiconductors are most commonly doped with boron, utilizing diborane (B₂H₆). However, the addition of boron to a stressor region, such as, for example, to a silicon germanium stressor region, may decrease the overall strain imposed by the stressor region, resulting in a reduction in carrier mobility and consequently a reduction in semiconductor device performance. The novel Group IIIA dopants described herein also allow for a reduction in electrical contact resistance with a semiconductor device structure, such as, for example, a transistor structure.

The embodiments of the invention may also include methods for the selective deposition of Group IV semiconductor materials and particularly methods for the selective deposition of highly p-type doped Group IV semiconductor materials. Common selective deposition processes may be achieved by the addition of an etchant gas, such as hydrochloric acid (HCl), to the deposition precursors during the deposition process. However, simplified processes which do not require the addition of further etchant gas may be desirable. Therefore novel methods are desired which enable selective deposition of highly p-type Group IV semiconductor materials.

The methods of the disclosure may be understood with reference to FIG. 1 which illustrates a non-limiting example embodiment of a method for forming a Group IV semiconductor. For example, FIG. 1 may illustrate an exemplary method 100 for forming a Group IV semiconductor, which may comprise a process block 110, wherein a substrate may be provided into a reaction chamber and the substrate may be heated to a deposition temperature within the reaction chamber. As a non-limiting example, the reaction chamber may comprise a reaction chamber of a chemical vapor deposition system. Embodiments of the present disclosure may be performed in a chemical vapor deposition system available from ASM International N.V. under the name Intrepid™ XP or Epsilon®. However, it is also contemplated that other reaction chambers, such as, for example, atomic layer deposition reaction chambers, and alternative chemical vapor deposition system from other manufacturers may also be utilized to perform the embodiments of the present disclosure.

In some embodiments of the invention, the substrate may comprise a planar substrate or a patterned substrate. Patterned substrates may comprise substrates that may include semiconductor device structures formed into or onto a surface of the substrate, for example, the patterned substrates may comprise partially fabricated semiconductor device structures such as transistors and memory elements. The substrate may contain monocrystalline surfaces and/or one or more secondary surfaces that may comprise a non-monocrystalline surface, such as a polycrystalline surface and an amorphous surface. Monocrystalline surfaces may comprise, for example, one or more of silicon (Si), silicon germanium (SiGe), germanium tin (GeSn), or germanium (Ge). Polycrystalline or amorphous surfaces may include dielectric materials, such as oxides, oxynitrides or nitrides, such as, for example, silicon oxides, and silicon nitrides.

With continued reference to FIG. 1, the method 100 may continue by heating the substrate to a desired deposition temperature within a reaction chamber. In some embodiments of the invention, the method 100 may comprise heating the substrate to a temperature of less than approximately 700° C., or to a temperature of less than approximately 600° C., or to a temperature of less than approximately 500° C., or to a temperature of less than approximately 400° C., or even to a temperature of less than approximately 300° C. For example, in some embodiments of the invention, heating the substrate to a deposition temperature may comprise heating the substrate to a temperature of between approximately 280° C. and approximately 700° C.

Once the substrate is heated to the desired deposition temperature, the method 100 may continue by exposing the substrate to one or more deposition precursors, which may comprise one or more precursors for depositing a Group IV semiconductor and may also comprise one or more precursors for doping the Group IV semiconductor with one or more p-type dopants.

Therefore, the methods of the disclosure may comprise exposing the substrate to at least one Group IV precursor, as illustrated by a process block 120 of FIG. 1. In some embodiments, exposing the substrate to at least one Group IV precursor may further comprise selecting the at least one Group IV precursor to comprise at least one of: silane (SiH₄), disilane (Si₂H₆), trisilane (Si₃H₈), tetrasilane (Si₄H₁₀), isopentasilane (Si₅H₁₂), neopentasilane (Si₅H₁₂), dichlorosilane (DCS), germane (GeH₄), digermane (Ge₂H₆), trigermane (Ge₃H₈), germylsilane (GeH₆Si), tin tetrachloride (SnCl₄), or methylsilane (CH₃—SiH₃).

In some embodiments, a single Group IV precursor may be utilized during the deposition process, for example, a single Group IV precursor may be utilized when the Group IV semiconductor to be deposited comprises silicon (Si) or germanium (Ge). In some embodiments, two or more Group IV precursors may be utilized during the deposition process, for example, two or more Group IV precursors may be utilized when the Group IV semiconductor to be deposited comprises a Group IV semiconductor alloy, including, but not limited to, silicon germanium carbide (Si_(1-x-y)Ge_(x)C_(y)), germanium tin (Ge_(1-x)Sn_(x)), germanium silicon tin (Ge_(1-x-y) Si_(x)Sn_(y)), germanium silicon tin carbide (Ge_(1-x-y)Si_(x)Sn_(y)C_(x)), silicon tin (Si_(1-x)Sn_(x)), silicon tin carbide (Si_(1-x-y)Sn_(x)C_(y)), or silicon carbide (Si_(1-x)C_(x)).

The deposition process for depositing a Group IV semiconductor may also comprise exposing the substrate to at least one Group IIIA halide dopant precursor. For example, in some embodiments of the invention the deposition method 100 as illustrated in FIG. 1, may comprise exposing the substrate to at least one Group IV precursor while simultaneously exposing the substrate to at least one Group IIIA halide dopant precursor, i.e., the Group IV precursor and the Group IIIA halide dopant precursor are co-flowed into the reaction chamber and react/decompose over a surface of the substrate disposed with the reaction chamber. The co-flow of the one or more Group IV precursors and the one or more Group IIIA halide dopant precursors into the reaction chamber may be utilized to enable the dopant species to be incorporated into the Group IV semiconductor as it is deposited.

In some embodiments, exposing the substrate to at least one Group IIIA halide dopant precursor may comprise selecting the at least one Group IIIA halide dopant precursor to comprise at least one of: a gallium dopant, an aluminum dopant, or an indium dopant.

In some embodiments of the invention, exposing the substrate to at least one Group IIIA halide dopant source further comprises selecting the at least one Group IIIA halide dopant precursor to comprise gallium trichloride (GaCl₃). In some embodiments of the invention, exposing the substrate to at least one Group IIIA halide dopant source further comprises selecting the at least one Group IIIA halide dopant precursor to comprise aluminum trichloride (AlCl₃). In some embodiments of the invention, exposing the substrate to at least one Group IIIA halide dopant precursor further comprises selecting the at least one Group IIIA halide dopant precursor to comprise indium trichloride (InCl₃).

In some embodiments of the invention, exposing the substrate to at least one Group IIIA halide dopant precursor further comprises selecting the Group IIIA halide dopant precursor to comprise a halide having the general formula Z_(x)MY_(3-x), wherein Z is independently chosen form hydrogen, deuterium, chlorine, bromine, and iodine, M is a Group III metal independently chosen from gallium, aluminum, and indium, Y is a halide independently chosen from chlorine, bromine, and iodine, and x is an integer from 0-3. In some embodiments of the invention, the Group IIIA halide dopant precursor may be in a dimer form. Therefore exposing the substrate to at least one Group IIIA halide dopant precursor further comprises selecting the Group IIIA halide dopant precursor to comprise a halide having the general formula (Z_(x)MY_(3-x))₂, wherein Z is independently chosen from hydrogen, deuterium, chlorine, bromine, and iodine, M is Group IIIA metal independently chosen from gallium, aluminum, and indium, Y is a halide independently chosen from chlorine, bromine, and iodine; and x is an integer from 0-3.

In some embodiments of the invention, exposing the substrate to at least one Group IIIA halide dopant precursor further comprises selecting the Group IIIA halide dopant precursor to comprise an organohalide having the formula R_(x)MY_(3-x), wherein R is independently chosen from CH₃, C₂H₅, C₆H₅, CF₃SO₃, and NH₂, M is group IIIA metal independently chosen from gallium, aluminum, and indium, Y is a halide independently chosen from chlorine, bromine, and iodine, and x is an integer from 0-3.

The selection of the Group IIIA halide dopant precursors comprising an organic component (e.g., an organohalide) may be further beneficial in the deposition of Group IV semiconductors. For example, carbon incorporation into a Group IV semiconductor may allow for further strain engineering in the Group IV semiconductor being deposited. Therefore, in some embodiments of the invention exposing the substrate to at least one Group IIIA halide dopant precursor further comprises incorporating carbon into the deposited Group IV semiconductor, the atomic percentage (at-%) of carbon in the Group IV semiconductor being greater than approximately 0.5% at-%.

The embodiments of the invention may continue with a process block 140 of FIG. 1, wherein a Group IV semiconductor may be selectively deposited on a surface of the substrate disposed within the reaction chamber. In more detail, the surface of the substrate may comprise one or more monocrystalline surfaces and one or more non-monocrystalline surfaces. For example, the one or more monocrystalline surfaces of the substrate may comprise a monocrystalline surface of at least one of: silicon (Si), germanium (Ge), silicon germanium (Si_(1-x)Ge_(x)), silicon germanium carbide (Si_(1-x-y)Ge_(x)C_(y)), germanium tin (Ge_(1-x)), germanium silicon tin (Ge_(1-x-y)Si_(x)Sn_(y)), germanium silicon tin carbide (Ge_(1-x-y)Si_(x)Sn_(y)C_(x)), silicon tin (Si_(1-x)Sn_(x)), silicon tin carbide (Si_(1-x-y)Sn_(x)C_(y)), or silicon carbide (Si_(1-x)C_(x)). In contrast, the one or more non-monocrystalline surfaces may comprise a non-monocrystalline surface of at least one of: a silicon oxide, a silicon nitride, a silicon oxynitride, a silicon oxycarbide, or a silicon oxycarbide nitride.

In some embodiments of the invention, selectively depositing the Group IV semiconductor on the surface of the substrate further comprises selectively depositing the Group IV semiconductor on one or more monocrystalline regions of the substrate. In other words, the selective deposition process preferentially deposits epitaxial Group IV semiconductor on the monocrystalline surfaces of the substrate while substantially no, or no deposition, occurs over the non-monocrystalline surfaces of the substrate.

A common method for enabling selective deposition of semiconductor materials is to add an etchant gas, such as, for example, hydrochloric acid (HCl) or chlorine (Cl₂), to the deposition precursor gas mixture. In contrast, the embodiments of the current disclosure generate an etchant species from the Group IIIA halide dopant precursor, thereby eliminating the need to add a further etchant gas to the deposition precursor gas mixtures. For example, in some embodiments exposing the substrate to at least one Group IIIA halide dopant precursor further comprises either decomposing and/or reacting the Group IIIA halide in the reaction chamber to produce an etchant species.

The etchant species generated from the Group IIIA halide dopant precursor may be utilized to produce a selective deposition process by selectively etching any Group IV deposition on the non-monocrystalline surfaces of the substrate. Therefore, in some embodiments of the invention, selectively depositing the Group IV semiconductor on the surface of the substrate further comprises selectively etching one or more non-monocrystalline regions of the Group IV semiconductor utilizing the etchant species. In some embodiments of the invention, the etchant species may comprise a halogen and may further comprise chlorine.

In some embodiments, selectively depositing a Group IV semiconductor on the monocrystalline surfaces of the substrate comprises, depositing at least one of: silicon (Si), germanium (Ge), silicon germanium (Si_(1-x)Ge_(x)), silicon germanium carbide (Si_(1-x-y)Ge_(x)C_(y)), germanium tin (Ge_(1-x)Sn_(x)), germanium silicon tin (Ge_(1-x-y)Si_(x)Sn_(y)), germanium silicon tin carbide (Ge_(1-x-y)Si_(x)Sn_(y)C_(x)), silicon tin (Si_(1-x)Sn_(x)), silicon tin carbide (Si_(1-x-y)Sn_(x)C_(y)), or silicon carbide (Si_(1-x)C_(x)).

The methods of the disclosure allow the Group IV semiconductor to be selectively deposited with a high concentration of p-type dopants without reducing the crystalline quality of the Group IV semiconductor. For example, in some embodiments, selectively depositing a Group IV semiconductor on the surface of the substrate further comprises selectively depositing the Group IV semiconductor with a doping concentration of greater than approximately 1×10²⁰ carriers per cubic centimeter, or greater than approximately 2.5×10²⁰ carriers per cubic centimeter, or even greater than approximately 5×10²⁰ carriers per cubic centimeter.

The embodiments of the invention may also provide semiconductor device structures comprising a Group IV semiconductor deposited by the methods described herein. For example, FIG. 2 illustrates a non-limiting example of a semiconductor device structure 200, wherein the semiconductor device structure 200 comprises a double gate MOSFET, commonly referred to as a FinFET. The semiconductor device structure 200 may comprise a substrate 202, which may comprise a bulk silicon (Si) substrate. The substrate 202 may be doped either with p-type dopants (for NMOS type FinFET devices) or with n-type dopants (for PMOS type FinFET devices). In the non-limiting example semiconductor device structure of FIG. 2, the substrate 202 may comprise n-type dopants and the semiconductor device structure 200 may comprise a PMOS FinFET.

The semiconductor device structure 200 may also comprise isolation regions 204, which may comprise shallow trench isolation (STI) regions. The semiconductor device structure 200 may also comprise a Fin structure 206 extending over the top surfaces of the isolation regions 204. A gate dielectric may be disposed over the sidewalls of the Fin structure 206 (not shown) and the gate dielectric may comprise a silicon oxide or a high-k dielectric material. A gate electrode 208 may be disposed on the gate dielectric for providing electrical contact to the channel region within the Fin structure 206. The semiconductor device structure 200 may also comprise gate spacers 210 which are disposed on the sidewalls of the gate electrode 208.

In some embodiments of the invention, the semiconductor device structure 200 may further comprise p-type Group IV semiconductor stressor regions 212A and 212B deposited over the source and drain regions of the FinFET device. It should be noted that the p-type stressor regions 212A and 212B may comprise a number of facets that may result due to the difference in growth rates on the different facets of the Fin structure 206. In non-limiting example embodiments of the invention, the p-type stressor regions 212A and 212B may be deposited utilizing the embodiments of the invention described herein. For example, the p-type stressor regions 212A and 212B may comprise silicon germanium (Si_(1-x)Ge_(x)) wherein the germanium composition in the silicon germanium stressor regions may be greater than approximately x>0.20, or greater than approximately x>0.50, or greater than approximately x>0.75, or even approximately x=1.0. In addition, the p-type stressor regions 212A and 212B may be doped according to the embodiments of the current disclosure and therefore the p-type stressor regions 212A and 212B may comprise a p-type doping concentration of greater than approximately 1×10²⁰ carriers per cubic centimeter, or greater than approximately 2.5×10²⁰ carriers per cubic centimeter, or even greater than approximately 5×10²⁰ carriers per cubic centimeter.

In some embodiments of the invention, an electrical contact may be made to the p-type Group IV semiconductor stressor regions 212A and 212B deposited over the source and drain regions of the FinFET device illustrated in FIG. 2. In some embodiments, the electrical contact (not shown) may comprise a silicide, such as, for example, a titanium silicide (TiSi₂). The embodiments of the invention allow for a high concentration of active p-type carriers in the source and drain stressor regions 212A and 212B which in turn may result in a reduction in the electrical contact resistance to the stressor regions. For example, the methods of the disclosure may comprise forming an electrical contact to the p-type stressor regions 212A and 212B, wherein the electrical contact has an electrical resistivity of less than 1×10⁻⁹ Ohm·cm², or less than 5×10⁻⁹ Ohm·cm², or even less than 1×10⁻⁸ Ohm·cm².

It should be noted that a non-limiting example embodiment given herein relates to p-type stressor regions formed over the source and drain regions of a FinFET device. However, the embodiments of the invention may be utilized for other purposes, for example, the p-type Group IV semiconductors deposited by the embodiments of the invention may be utilized to induce stress in other areas of a device structure, for example, by depositing a p-type stressor region over the channel region of a transistor to thereby induce strain directly in the channel region of the transistor device structure.

The example embodiments of the invention described above do not limit the scope of the invention, since these embodiments are merely examples of the embodiments of the invention, which is defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the disclosure, in addition to those shown and described herein, such as alternative useful combination of the elements described, may become apparent to those skilled in the art from the description. Such modifications and embodiments are also intended to fall within the scope of the appended claims. 

What is claimed is:
 1. A method of selectively depositing a Group IV semiconductor on a surface of a substrate comprising: providing the substrate within a reaction chamber; heating the substrate to a deposition temperature of less than 600° C.; exposing the substrate to at least one Group IV precursor; and exposing the substrate to at least one Group IIIA halide dopant precursor, wherein the at least one Group IIIA halide dopant precursor generates an etchant species, and wherein the method of selectively depositing the Group IV semiconductor does not include exposing the substrate to an additional etchant.
 2. The method of claim 1, further comprising selecting the at least one Group IIIA halide dopant precursor to comprise gallium trichloride (GaCl₃).
 3. The method of claim 1, further comprising selecting the at least one Group IIIA halide dopant precursor to comprise aluminum trichloride (AlCl₃).
 4. The method of claim 1, further comprising selecting the at least one Group IIIA halide dopant precursor to comprise indium trichloride (InCl₃).
 5. The method of claim 1, further comprising selecting the Group IIIA halide dopant precursor to comprise a halide having the general formula Z_(x)MY_(3-x), wherein Z is independently chosen from hydrogen, deuterium, chlorine, bromine, and iodine; M is a Group III metal independently chosen from gallium, aluminum, and indium; Y is a halide independently chosen from chlorine, bromine, and iodine; and x is an integer from 0-3.
 6. The method of claim 1, further comprising selecting the Group IIIA halide dopant precursor to comprise a halide having the general formula (Z_(x)MY_(3-x))₂, wherein Z is independently chosen from hydrogen, deuterium, chlorine, bromine, and iodine; M is Group IIIA metal independently chosen from gallium, aluminum, and indium; Y is a halide independently chosen from chlorine, bromine, and iodine; and x is an integer from 0-3.
 7. The method of claim 1, further comprising selecting the Group IIIA halide dopant precursor to comprise an organohalide having the general formula R_(x)MY_(3-x), wherein R is independently chosen from CH₃, C₂H₅, C₆H₅, CF₃SO₃, and NH₂; M is group IIIA metal independently chosen from gallium, aluminum, and indium; Y is a halide independently chosen from chlorine, bromine, and iodine; and x is an integer from 0-3.
 8. The method of claim 7, wherein exposing the substrate to an organohalide further comprises incorporating carbon into the deposited Group IV semiconductor, the atomic percentage of carbon in the Group IV semiconductor being greater than approximately 0.5 at-%.
 9. The method of claim 1, wherein heating the substrate to a deposition temperature comprises heating the substrate to a temperature of less than 400° C.
 10. The method of claim 1, wherein exposing the substrate to at least one Group IV precursor further comprises selecting the at least one Group IV precursor to comprise silane (SiH₄), trisilane (Si₃H₈), tetrasilane (Si₄H₁₀), isopentasilane (Si₅H₁₂), neopentasilane (Si₅H₁₂), dichlorosilane (DCS), germane (GeH₄), digermane (Ge₂H₆), trigermane (Ge₃H₈), germylsilane (GeH₆Si), tin tetrachloride (SnCl₄), or methylsilane (CH₃—SiH₃).
 11. The method of claim 1, wherein depositing a Group IV semiconductor on a surface of the substrate further comprises depositing at least one of silicon (Si), germanium (Ge), silicon germanium (Si_(1-x)Ge_(x)), silicon germanium carbide (Si_(1-x-y)Ge_(x)C_(y)), germanium tin (Ge_(1-x)Sn_(x)), germanium silicon tin (Ge_(1-x-y)Si_(x)Sn_(y)), germanium silicon tin carbide (Ge_(1-x-y)Si_(x)Sn_(y)C_(x)), silicon tin (Si_(1-x)Sn_(x)), silicon tin carbide (Si_(1-x-y)Sn_(x)C_(y)), or silicon carbide (Si_(1-x)C_(x)).
 12. The method of claim 1, wherein depositing a Group IV semiconductor on a surface of the substrate further comprises depositing the Group IV semiconductor with a doping concentration of greater than approximately 1×10²⁰ carriers per cubic centimeter.
 13. The method of claim 1, wherein exposing the substrate to at least one Group IIIA halide dopant precursor further comprises either decomposing and/or reacting the Group IIIA halide in the reaction chamber to produce the etchant species.
 14. The method of claim 13, wherein selectively depositing the Group IV semiconductor on the surface of the substrate further comprises selectively etching one or more non-monocrystalline regions of the Group IV semiconductor utilizing the etchant species.
 15. The method of claim 14, wherein selectively depositing the Group IV semiconductor on the surface of the substrate further comprises selectively depositing the Group IV semiconductor on one or more monocrystalline surfaces of the substrate.
 16. The method of claim 14, wherein the etchant species comprises a halogen.
 17. The method of claim 16, wherein the halogen comprises chlorine.
 18. A semiconductor device structure comprising the Group IV semiconductor deposited according to the method of claim
 1. 19. The semiconductor device structure of claim 18, wherein the Group IV semiconductor comprises a p-type stressor region.
 20. The semiconductor device structure of claim 19, further comprising forming an electrical contact to the p-type stressor region, wherein the electrical contact has an electrical resistivity of less than 1×10⁻⁸ Ohm·cm². 